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Airworx:This is actually called the suction cutt-off unloader,that is activated by a solenoid,but not really sure how or what the proper sequence of operation is,I do know that is has to do with capacity control,but no sure what or at what point does it unloads or loads up.Any input would be appreciated.

unloaders help us to overcome low load situations where keeping the system running to maintain humidity or low tempertures will drop the suction pressure below the freeze point like 58 lbs dx and 55 lb chillwater.

If it`s the unloaders you are asking about, They re controlled by the processor. If you have 2 compressors each with one unloader. There is a dip switch setting on the micro that should be set for 4 step cooling. 2 compressor with no unloaders it should be set for 2 step cooling. The micro processor determines how many stages are to be on by how far away from setpoint the room is.

Typically it's not an unloader. It's your normal everyday liquid line solenoid valve. Most Lieberts use a pump down method to stop the compressor(s). The LL valve is controlled by the units main microprocessor and has a certain sequence of events.

What are you trying to attempt that you need to know this info?

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